Improving Productivity and Efficiencies on an Automated Bottling Line in the Beverage Industry. JA Jooste

Transcription

1 Improving Productivity and Efficiencies on an Automated Bottling Line in the Beverage Industry by JA Jooste Submitted in partial fulfilment of the requirements for the degree of Bachelors in Industrial Engineering in the Faculty of Engineering, Building Environment & Information Technology University of Pretoria Pretoria 23 October 2008 i

2 Executive Summary Nestlé was established in 1843 by Henri Nestle when he constructed his first lemonade bottling factory. Since 1843 Nestle has grown to be the world s largest food company with nutrition as the company s corner stone. Nestle Waters became one of the major players in the bottled water industry in South Africa through its Valvita and Schoonspruit brands. This project will focus on the Sparkling and Flavoured Water Bottling Line at Nestle Waters where carbonated water and flavoured carbonated water is bottled. The company has established that the Sparkling and Flavoured Water Bottling Line had an efficiency of 29.56% during the production year of Various factors were identified which contributed to the low efficiency levels of the production lines. These factors include: machine breakdowns, minor stoppages, long changeover times and process delays. The aim of this project was to increase the productivity and efficiency of the bottling line and decrease operational costs by identifying possible maintenance procedures to decrease equipment failures and focussing on the improvement of the changeover processes, eliminating minor stoppages and process delays on the production line. The primary production losses have been analysed by utilizing Total Productive Maintenance (TPM) approaches. Methods such as Phenomenon-Mechanism (P-M) Analysis, Operational Analysis techniques and Single Minute Exchange of Die (SMED) concepts have been used in conjunction with Total Productive Maintenance (TPM) to analyse the production losses. Basic maintenance programs have been discussed to prevent equipment failures and rate losses on the production line, Phenomenon-Mechanism (P-M) Analysis was used to establish minor stoppage causes on the production line and identify possible solutions to eliminate the minor stoppage losses, and Single Minute Exchange of Die (SMED) techniques were used to improve changeover processes on the Sparkling and Flavoured Water Bottling Line. The implementation of the suggestions developed for the improvement of the changeover processes will increase the production capacity of the Sparkling and Flavoured Bottling Line by an estimated 19 34% OR litres of carbonated and flavoured carbonated water per year. ii

3 Table of Contents Executive Summary...ii 1. Introduction and Company Background Problem Statement Project Aim Project Scope Project Deliverables Literature Review Literature Resources Literature Overview Operation Analysis Total Productive Maintenance (TPM) Phenomenon-Mechanism Analysis (P-M Analysis) Single Minute Exchange of Dies (SMED) Data and Information Gathering Processes and events at Nestle Waters Current Production State of Nestlé Waters Data analysis and interpretation Equipment failures and breakdowns Minor Stoppages Long Changeover Times Rate Losses/Reduced Capacity Losses Problem Solving Total Productivity Maintenance (TPM) Equipment Failures and Breakdowns Rate Losses/Reduced Capacity Losses Phenomenon-Mechanism Analysis (P-M Analysis) Step 1: Clarify the Phenomenon Step 2: Conduct a physical analysis iii

4 Step 3: Causal Factors of the Minor Stoppages Step 4: Cause and Effect Analysis Step 5: Propose and make improvements Single Minute Exchange of Dies Stage 1: Separating External and Internal Setups Stage 2 & 3: Convert Internal Setups to External Setups and Streamline Setup activities Evaluation and Recommendation Equipment Failures and Breakdown Solutions Minor Stoppage Solutions Changeover Solutions Final Recommendations Conclusion References Apendices List of Figures Fig.1 Major processes used in Nestlé s water bottling lines Fig. 2 Operation Analysis technique ( Why Analysis )... 6 Fig. 3 Phases in the P-M Analysis (Cigolini and Rossi 2004) Fig. 4 Hierarchy of changeover concepts, techniques and examples (McIntosh et al 2000) 16 Fig. 5 SMED conceptual stages and practical techniques (McIntosh et al 2000) Fig. 6 Availability of Line Fig. 7 Availability of Line Fig. 8 Availability of Line Fig. 9 The productive hours and downtime hour s fractions for line Fig. 10 Cause and Effect Diagram for Equipment failures and breakdowns Fig. 11 Pareto Chart based on Total Downtime of Line iv

5 Fig. 12 Machine Contribution to Total Downtime on Line Fig. 13 Pareto Chart based on Minor Stoppages for Line Fig. 14 Machine Contribution to Minor Stoppages in Line Fig. 15 Contributions to Minor Stoppages on Line Fig. 16 The changeover times on line Fig. 17 Gantt chart representing the changeover tasks of the filler Fig. 18 Gantt chart representing the changeover tasks for the Filler Fig. 19 Gantt chart representing the changeover tasks for the Unscrambler Fig. 20 Dimensions of the Unscrambler pockets Fig. 21 Gantt chart representing the changeover tasks for the Filler Fig. 22 Gantt chart representing the changeover tasks for the Unscrambler Fig. 23 Preventive Maintenance Techniques Fig. 24 Toolbox for each operator Fig. 25 Colour coded lubrication points Fig. 26 Filling Machine Fig. 27 Bottle Unscrambler Fig. 28 Cause and Effect Diagram for the minor stoppages on the Filler Fig. 29 Suggested improvements on the Filler bottle controls Fig. 30 Neck Clamps improvements Fig. 31 Illustration of the platform with both bottle diameter patterns Fig. 32 Storage areas for changeover components Fig. 33 Proposed trolley...71 Fig. 34 Proposed storage compartment Fig. 35 Functional clamp for the starwheels Fig. 36 Locking Cam to fix bottle guides to Filler and Unscrambler Fig. 37 Production capacity increase with one changeover v

6 List of Tables Table 1 Critical Analysis technique... 7 Table 2 Improvement techniques within the SMED framework (McIntosh 2007) Table 3 Minor Stoppages experienced on Line Table 4 Original design capacities of machines utilized in Line Table 5 Parameters used for Predictive Maintenance Table 6 Filler operations physical descriptions Table 7 Unscrambler operations physical description Table 8 Minor Stoppages on the Filler Table 9 Minor stoppages on the Unscrambler Table 10 Causes of the minor stoppages on the Filler Table 11 Causes of the minor stoppages on the Unscrambler Table 12 Minor stoppage improvements on the Filler Table 13 Minor Stoppage Improvements on the Unscrambler Table 14 Current changeover activities on the Filler Table 15 Current changeover activities on the Filler Table 16 Current changeover activities on the Unscrambler Table 17 Suggested Water flavour changeover activities Table 18 Changeover activities and time durations after changeover improvements Table 19 Changeover activities and time durations after changeover improvements Table 20 Examples of TPM Effectiveness (Recipients of the PM prize) Table 21 Increased production capacity (Litres Water) with decrease in Minor Stoppages. 76 vi

7 1. Introduction and Company Background Nestlé was established in 1843 by Henri Nestlé when he constructed his first lemonade bottling factory. Since 1843 Nestlé has grown to be the world s largest food company with nutrition as the company s corner stone. A brief history of Nestlé Waters South Africa: In 1987 Nestlé South Africa took a majority stake in the Société Générale des Eaux Minérales de Vittel (General Society for Mineral Waters from Vittel) In 1996 Perrier Vittel SA was borne In 2002 Perrier Vittel became part of Nestlé Waters Nestlé Waters became one of the major players in the bottled water industry in South Africa through its Valvita and Schoonspruit brands. One of Nestlé Waters most important assets is the Doornkloof plant near Olifantsfontein. The aquifer in the underlying dolomite produces one of the finest natural mineral waters in the world. Nestlé Waters Doornkloof is currently utilising three water bottling lines for the production of bottled water. During 2007, Nestlé Waters Doornkloof bottled litres of water. Due to the time limitations, the project will focus on Line 1 (Sparkling and Flavoured water line). The principles and solutions created for the project on line 1 will be applied to the other two lines. Line 1 (Sparkling and Flavoured water line) is dedicated to produce the following products: 500ml Sparkling Water 1.5litre Sparkling Water 500ml & 1.5 litre Blackberry Flavoured Water 500ml & 1.5 litre Litchi Flavoured Water 500ml & 1.5 litre Lemon &Lime Flavoured Water 500ml & 1.5 litre Strawberry Flavoured Water 500ml & 1.5 litre Naartjie Flavoured Water 1

8 2. Problem Statement Nestlé Waters has identified the need to increase the productivity and efficiency of the bottling lines and increase the profitability of the company. A quick analysis of the efficiency for bottling line 1 during the past production year of 2007 showed that line 1 was nonoperational for 70.44% of the total production time. Machine breakdowns, minor stoppages, process delays and long changeover times are the four main contributions to the total idle time of the system. Machine breakdowns, minor stoppages and process delays contributed for 43.24% of the total production time and changeover times contributed for 26.20% of the total production time. Line 1 is utilising only 30% of its total production time due to the following factors: Utilization of second hand machines Lack of maintenance planning Using the emergency repair strategy Using Run Till Death (RTD) maintenance strategy on second hand machines Long changeover times between different flavours and bottle volumes 3. Project Aim The aim of this project is to increase the productivity and efficiency of the bottling line and decrease operational costs which will in return increase the profitability of the company. The aim of the project will be achieved by developing and implementing improved maintenance procedures and improving the current changeover techniques and times. The enhancements will have the following benefits to the company: Detection of pending failures before they happen Reparation of defective parts Monitoring of conditions and failure causes Assessment of equipment on a fixed interval basis Prevention of failures Decrease in machine downtime Quicker changeover times The enhancements in the process delays and changeover times, and the prevention of failures through maintenance management will ensure an increase in productivity and efficiency, reduced operating costs, increases in profitability and it will create a better morale amongst the employees. 2

9 4. Project Scope The intended scope of this project will cover activities directly related to the Sparkling and Flavoured water bottling line (Line 1). Fig.1 Major processes used in Nestlé s water bottling lines. Shrink Wrapper Palletizing Labelling Machine Rinser Filling Table Slat Conveyor Still Water Bottling Line Filler (Line 2 Filler) Line 1 Filling Machine Scrollers Bottle Capper Air Conveyor Rail Bottle Unscrabler Bottle Shute Elevator Loading Dock for the bottles Special attention will be given to the changeover techniques as well as the maintenance procedures of the machines used in the production system. The project will include the views from the extraction process of the water through to the warehousing processes. Other areas and factors that will be considered: Time in System Production system capacity Bottling line efficiencies Bottling line speeds Production schedules Inventory management Utilization Product Quality Production floor layout Material handling Nestlé Quality Standards 3

10 5. Project Deliverables The project deliverables will include: Process flow chart with all processes Pareto Charts with the causes of downtimes Downtime improvement suggestions New improved changeover principles and methods Quicker changeover times Improved Maintenance Management Bigger production throughput Increase in productivity Increase in profitability 4

11 6. Literature Review 6.1. Literature Resources Information is available in a number of formats. It is important for you to understand the significance of various formats so that you know what will best suit your information requirements. The following resource formats are commonly used: Internet Books Articles Manuals Notes Interviews Discussions News footage Observations Notice boards 6.2. Literature Overview The primary objectives of this project are to increase the productivity and efficiency of the bottling line and decrease operational costs which will in return increase the profitability of the company. Due to the complexity and variety of the machine breakdowns, minor stoppages, process delays and long changeover times, it is necessary to get a clear understanding of the core problems and the causes of these problem areas on the Sparkling and Flavoured Water bottling line. According to Cigolini and Rossi (2004), automated production lines have been designed for a required capacity or production rate and minor stoppages due to failures, defects etc. are to be avoided at all times, since the connected losses of production have a relevant impact on the overall manufacturing cost, and ultimately on final customers since the time the machines spend in non-productive activities reduces the time available for value generation. 5

12 Extensive research was done to establish suitable methods and strategies to implement in the company to improve the productivity of the bottling line, after the core problem areas in the production facility were identified. To achieve this, relevant literature has to be reviewed, analysed and applied. The literature research delivered the following methods that can be utilized to address the core problem areas: Operation Analysis Total Productive Maintenance (TPM) Phenomenon-Mechanism Analysis (P-M Analysis) Single Minute Exchange of Dies (SMED) Operation Analysis Operational analysis is used to study all productive and non-productive elements of an operation, to increase productivity per unit of time, and to reduce unit costs while maintaining or improving quality (Niebel and Freivalds 2003). Operational analysis can be used for planning new workstations or improving current production lines that is in operation. Operational analysis develops better methods and simpler operational procedures for the current equipment utilized. When operation analysis is properly utilized the company will be able to increase the production output and decrease the unit cost. Operation analysis is based on asking the five questions. The most important question of these five questions is the question Why. The question Why immediately suggests other questions including; How, Who, Where, and When. Figure 2 indicates an example of these questions. Fig. 2 Operation Analysis technique ( Why Analysis ) 6

13 Table 1 is a critical analysis template that will aid in the operation analysis process. Table 1 Critical Analysis technique METHOD: PRESENT METHOD CRITICAL ANALYSIS TECHNIQUE ALTERNATIVES SELECTED ALTERNATIVE Purpose: What is achieved? Is it necessary? Why? What else could be done? What is the purpose? Means: How is it done? Why that way? How else could it be done? How should it be done? Place: Where is it done? Why there? Where else can it be done? Where should it be done? Sequence: When is it done? Why then? When else could it be done? When should it be done? Person: Who does it? Why that person? Who else could do it? Who should do it? Total Productive Maintenance (TPM) Cigolini and Rossi (2004) states that the TPM approach is a methodological pattern to increase automated lines productivity by minimizing production losses. TPM is a production management approach, basically oriented to maximize the overall machine productivity, to define and implement a preventive maintenance plan for the life cycle of each machine and to involve all the company functions (Cigolini and Rossi 2004). According to Cigolini and Rossi (2004), the first two objectives of TPM consist basically in eliminating all the types of production losses and that the TPM procedures, almost all of the ones developed by the Japan Institute of Plant Maintenance, deal with breakdowns, setup, speed losses, defective quality, yield losses and minor stoppages. According to the Total Productive Maintenance (TPM) approach, production losses can be categorised into six main areas (see e.g. Nakajima 1988, Wireman 1991): 1. Breakdown losses 2. Set-up and adjustment losses 3. Idling and minor stoppages 4. Reduced capacity losses 5. Defective quality and re-work 6. Start-up/restart losses 7

14 Breakdown losses There are two major types of breakdown losses according to Nakajima (1988): capacity loss breakdowns and capacity reduction breakdowns. Capacity loss breakdowns are equipment that ceases to operate (also called a machine breakdown) and are thus the easiest to recognize and identify. Capacity reduction breakdown is caused by the ageing of the equipment that is used for production purposes; with the ageing of equipment the components of the equipment experiences wear. As the wear of the equipment continues to increase, the designed capacity of the equipment starts to decrease. The reduction in the capacity and productivity due to the wear of equipment goes unnoticed and is accepted as normal because the careful monitoring of equipment wear doesn t occur. The capacity reduction breakdown translates into slower operation, a decrease in production capacities, and increased labour costs in the production process. Capacity reduction breakdown translates into higher energy and operational costs in facilities. While the capacity loss breakdown is the easiest to recognize and repair, the capacity reduction breakdown represents the largest cost to most companies. The capacity loss breakdown is in most cases a technical problem while the capacity reduction breakdown is in most cases an organizational problem. Capacity loss breakdowns are created by the failure of components on the equipment utilized. Although most preventive/predictive maintenance programs are created and designed to detect the normal wear on equipment, other types of wear cannot be detected and it will cause the majority of these breakdowns. Other types of breakdowns include infant mortality failures, and failures that are related to poor operating activities and poor maintenance programs. Most of these breakdowns can be prevented and minimized if the preventive/predictive maintenance program is effective. The capacity reduction breakdown is caused by neglecting chronic equipment problems that occur in the production lines. Chronic equipment problems are problems that occur over long periods of time and become accepted as a normal fact of operation. 8

15 According to Wireman (1991), a typical example would be equipment that produces a defective product when operating at any rate over 80% of design speed. Instead of taking the time and effort necessary to correct the problem, the organization will issue a memo stating not to run the equipment over 80% of design speed. This results in a 20% reduction in equipment capacity. By accepting these chronic problems and decreasing the operating speeds of the equipment each time the problems occur, the plant will need to replace the equipment with new equipment to meet the necessary production rates. These problems become severe due to the fact that management doesn t focus on the longterm goals but rather focussing on the short-term goals that needs to be achieved. It is more economical to solve the capacity reduction problems when they develop than to reduce the operating standards of the equipment to meet the required demands. It is a matter of examining the short-term profits in the light of long-term profitability Setup and Adjustment Losses Setup and adjustment losses are incurred when equipment is used to manufacture different products. The definition of setup and adjustment time is the period of time lost when the equipment is finished producing one product and is producing the next product at the specified quality (Nakajima 1988, Wireman 1991). The losses incurred due to the setup and adjustments that need to be done on a production line can be the difference between a profit and a loss for the company. For example, if the setup and adjustment times are reduced for a certain production line, the lot size which is economical to run for a certain product will be reduced. The reduction in the lot size increases the flexibility of the production scheduling and sales group. This increase will allow the production scheduling and sales group to be more responsive to customer requests Improvements in equipment setups and adjustments can be made in three clear areas: 1. External Setups these activities can take place while the equipment is in operation. 2. Internal Setups these activities can take place only while the equipment is shut down. 3. Adjustments these activities take place while trying to get the equipment to produce a quality product. 9

16 Idling and Minor Stoppages Idling and minor stoppages are caused by stopping the equipment for a few minutes due to equipment malfunction or when the equipment is idle for few minutes due to an upstream operation malfunction in the production line. These minor stoppages are ignored for most of the time due to the short times the equipment needs to be stopped to correct the problem. These stoppages are then accepted as a normal operational characteristic of the equipment over a period of time. In some cases these losses can be more than the losses caused by capacity loss breakdowns. The three main types of idling and stoppages are: 1. Overloads 2. Malfunctions of the equipment 3. Upstream malfunctions For example, if a piece of equipment experiences a total of 10 minutes of stoppages per shift, on a 3 shift per day operation and running for 5 days per week, the total downtime per month experienced by the piece of equipment will accumulate to 10 hours (Wireman 1991). The cost of idle and minor stoppage losses can easily amount to enormous costs when you consider what the cost of one hour of downtime on a piece of equipment will be. In a bottling facility these costs multiply rapidly because the equipment is not standalone units but are connected by conveyors. The different equipment units rely on the units upstream from them. A delay on the first process will contribute to similar delays on the processes downstream. Most companies don t notice these small losses and in return don t correct them. These losses must be eliminated in order to have a cost effective production line Reduced Capacity Losses The reduced capacity losses are defined as the difference between the rated capacity of the equipment and the capacity at which it is operating (Wireman 1991). Equipment capacity is reduced by two main areas: the speed and volume of the output. The designed capacity of older equipment is usually unknown and the true speed and output of the equipment should be determined. The newly determined speed and output of the equipment should become the new capacity rating of the equipment. 10

17 All the minor problems that are experienced should be corrected in order to reach the new capacity rating of the equipment and the desired levels of production. As previously discussed, operations personnel accepts less than design capacity productions from their equipment over long periods of time. When a piece of equipment is experiencing a problem or failure it should not be limped to the next shutdown or outage. By limping the piece of equipment to the next shutdown or outage may cost more than taking it off the line and repairing the problem. The lost capacity, joined with increasing costs for operations and maintenance, will be greater than continuing the production process with the reduced production output. The rule to remember in this area is to not accept anything less than capacity rated performance from any equipment. If this rule is followed, all necessary steps will be taken to correct minor problems before they become major problems (Wireman 1991) Defective Quality and Re-work Maintenance-related quality problems can be divided into two categories: habitual and occasional defects. Habitual defects are caused by equipment that is operating with deterioration that the management has come to accept as normal operation. The deterioration of equipment is problems that have developed over a long period of time and are then neglected. These problems are usually compensated for by adjusting the equipment. The adjustments to the equipment in turn affects other systems on the equipment and results in a decrease in the operational standards. Habitual defects and quality-related problems will only be eliminated when the equipment is restored to its original operating standard. The occasional defects are caused by malfunctions that have suddenly developed during production. Occasional defects are caused by components that fail in one of the systems or parts of the equipment. The problem is easily noticeable and the corrective actions or reparation actions are quickly and easily determined. 11

18 Start-up/Restart Losses Each time the processes in the production line must be shut down and restarted, startup/restart losses are incurred. These start-up losses are incurred when unacceptable products are produced while the equipment is heating up to a certain standard operation temperature or a certain operating speed. The costs of lost production while the equipment was shutdown must include lost production while the start-up and shutdown were occurring. The time it takes to do the start-up and shutdowns accumulates to a huge amount of hours that are lost during a production run or occurrence Phenomenon-Mechanism Analysis (P-M Analysis) TPM procedures almost all of the ones developed by the Japan Institute of Plant Maintenance deal with breakdowns, set-up, speed losses, defective quality, yield losses and minor stoppages: they apply the so-called phenomenon mechanism (P M) analysis to the TPM procedures (Cigolini and Rossi 2004). The phenomenon (in the phenomenon-mechanism analysis) represents the abnormal event within the operational activities that needs to be controlled and the mechanism (in the phenomenon-mechanism analysis) represents the group of equipment elements with a common function. P-M analysis involves the understanding of what happens during the abnormal event and how it happens (e.g. when a stoppage occurs or a machine produces defective parts); then the causal factors of the abnormal event can be identified and addressed, and the losses can be eliminated. Figure 3 provides an overview of the eight basic steps involved in the P-M analysis. 12

19 Fig. 3 Phases in the P-M Analysis (Cigolini and Rossi 2004) 13

20 P M analysis is composed of eight steps (see figure 3): 1. Clarify the phenomenon - Specific guidelines are given for the observation and understanding of the phenomenon. 2. Conduct a physical analysis The object of the physical analysis is to explain how the phenomena occur in terms of physical and quantities 3. Define the phenomenon s constituent conditions This phase involves the identification of the conditions that are needed for the occurrence of the abnormal event. These conditions must be categorised into four production inputs, i.e. men, machines, materials and methods. 4. Study production input correlations - This step deals with the cause effect relationships between production inputs and conditions. This cause-effect analysis leads to the review of equipment, materials, methods and people. 5. Set the optimal standard values - Step 5 is concerned with the optimal conditions for each potential source of variance. 6. Survey causal factors for abnormalities - The sixth phase determines the most effective method to fill the gap between the actual condition and the optimal condition for each causal factor. 7. Determine abnormalities that need to be addressed the factors that actually generate variance can be pointed out and highlighted. 8. Propose and make improvements - corrections and improvements can be made Single Minute Exchange of Dies (SMED) Rapid changeover is identified also as being one of the six key focus areas of TPM (total productive maintenance) (Nakajima 1988). A rapid changeover capability is widely acknowledged as an essential prerequisite to flexible, responsive small batch manufacturing. Its importance in mass customization is recognized, where minimal losses need to be incurred as manufacture switches between differing products (McIntosh 2007). Changeover improvement is the completion of the changeovers between the manufacturing of different products more quickly and to higher standards. Changeovers are also referred to as setup reduction or setup reengineering. In today s competitive market more responsive and flexible production models are needed and to achieve this, the changeover frequency must remain high. 14

21 The duration of the changeover needs to be short for multilot production to be profitable. Rapid, high-quality changeovers are key instruments to improve competitiveness and assisting in the responsiveness to the external market demands and the internal control of factory operations. Two areas of production losses (namely setup and adjustment losses, and start-up/restart losses) are closely related and results from changeovers. SMED presents a quick and efficient way of changing a production process from producing the current product to producing the next product (Quick Changeovers). Quick changeovers make it possible to have low cost and flexible operations in the plant. The following improvements can be achieved by implementing SMED for quick changeovers: Improved flexibility Increased machine utilization Reduced setup times even if the number of changeovers increase Elimination of setup errors Elimination of trial runs Reduced defects Better and easier housekeeping Lower expenses of setups Reduced stock Figure 4 represents Shingo s broad discussion and presentation of the concepts, techniques and examples used in SMED as a hierarchical structure (McIntosh et al 2000). Figure 4 that is represented by McIntosh et al (2000) will assist in the decision making of where to initiate the SMED approach in the facility. 15

22 Fig. 4 Hierarchy of changeover concepts, techniques and examples (McIntosh et al 2000) There are four key phases of the improvement process that needs to be followed when starting the SMED methodology: Stage 0 - `Internal and external set-up conditions are not distinguished Stage 1 - `Separating internal and external set-up Stage 2 - `Converting internal to external set-up Stage 3 - `Streamlining all aspects of the set-up operation 16

23 Fig. 5 SMED conceptual stages and practical techniques (McIntosh et al 2000) The first stage of Figure 5 is only a report of the current situation in the production facility. Shingo proposes three concepts/stages, as shown in Table 2: 1. Separating internal and external set-up 2. Converting internal to external set-up 3. Streamlining all aspects of the set-up operation 17

24 Table 2 Improvement techniques within the SMED framework (McIntosh 2007) Shingo proposes twelve techniques that should be used in combination with the three phases (concepts), as shown in Table 2, when SMED is implemented. The external setup is a setup that is done while the equipment is still running. External setups will result in tools and parts that are prepared and corrected before the setup and changeover is done. Internal setups are setups that are carried out while the equipment is shutdown. Internal setups are changeovers where equipment components have to be replaced by other components. 18

25 7. Data and Information Gathering Before data and information can be gathered regarding the facility, one must first of all map, record and understand the processes and events that are followed in the facility to produce a quality product. The data and information gathering exercise should be done with the problem statement in mind. This will enable the analyst to identify possible problem areas in the production line that will need further investigation Processes and events at Nestle Waters The empty bottles are received in pallets from the various suppliers. The empty bottle pallets are then stored in the receiving area. The palletized empty bottles are fed by a forklift to the automated feeder where the palletized bottles are pushed into the Unscramble, level by level, by the automated feeder. The bottle Unscrambler orientates the bottles into an upright position which are then fed into the air conveyor and are transported to the filler and rinsing machine. The bottles are rinsed, filled with the recommended flavoured water and then the filled bottles are capped. Slat conveyors transport the filled bottles to the labeller where the correct labels are glued to the bottle. The labelled bottles are inspected by sensors and by the quality inspector for defects after which the conveyors feed the labelled bottles to the shrink-wrapping machine where they are grouped together (eight bottles are grouped for the 500ml bottles and six bottles are grouped for the 1.5l bottles) and shrink-wrapped into cases. These cases are then palletized by manual labour. The flavoured bottled water pallets are then transported to the final goods stores with a forklift Current Production State of Nestlé Waters Nestlé Waters forecasted a demand of 45 million litres of bottled water during the production year of 2007, but only managed to bottle a total of 35 million litres of water during the year. A quick investigation that looked into the problem of why Nestle Waters forecasted demand of 45 million litres of bottled water was not met revealed that during the production year of 2007 not one of the three bottling lines met their predetermined efficiency goals of 80%. The analysis revealed that the Sparkling and Flavoured Bottling Line (Line 1) was nonoperational for 70.44% of the total production time (operational for only 29.56% of the total production time). 19

26 The Still Water Bottling Line (Line 2) was non-operational for 56.89% of the total production time and the Bulk Still Water Bottling Line (Line 3) was non-operational for 40.83% of the total production time. There is a clear warning that there is a major problem with the efficiencies and productivity of the production lines of Nestlé Waters. Fig. 6 Availability of Line 1 Line 1: Total Changeover time as % of Total Production Hours 27.20% Net Production Hours as % of Total Production Hours 72.80% Breakdown Stoppages + Rate Loss Time+ Unexpected Time Losses as % of Total Production Hours 43.24% Total time line 1 is not running as % of Total Production Hours 70.44% Total Productive Hours as % of Total Production Hours 29.56% Fig. 7 Availability of Line 2 Line 2: Total Changeover time as % of Total Production Hours 22.94% Net Production Hours as % of Total Production Hours 77.06% Breakdown Stoppages + Rate Loss Time + Unexpected Time Losses (Machine downtime) as % of Total Production Hours 33.96% Total time line 2 is not running as % of Total Production Hours 56.89% Total Productive Hours as % of Total Production Hours 43.11% Fig. 8 Availability of Line 3 Line 3: Total Changeover time as % of Total Production Hours 22.27% Net Production Hours as % of Total Production Hours 77.73% Breakdown Stoppages + Rate Loss Time + Unexpected Time Losses (Machine downtime) as % of Total Production Hours 18.56% Total time line 3 is not running as % of Total Production Hours 40.83% Total Productive Hours as % of Total Production Hours 59.17% (Net Production Hours = Total Production Hours Changeover Time) 20

27 The availability of the different production lines is determined by the following formula (Nakajima 1988): Availability = Operating Time Loading Time The loading time represents the time that is available per year (month, week, day) for production and is derived by subtracting the planned downtime from the total available time per year (month, week, day). Operating time is derived by subtracting equipment downtime (non-operational time) from the loading time. It was decided that due to time limitations and the magnitude of the Sparkling and Flavoured Water Bottling Line s (Line 1) productivity and efficiency problems, the project will focus only on Line 1 (Sparkling and Flavoured water line). The principles and solutions created for the improvement of the productivity and efficiency of line 1 will be applied to the other two lines. Fig. 9 The productive hours and downtime hour s fractions for line 1 Productive Hours and Downtime Hours for Line 1 Rate Losses as % of Total Production Hours, 12.87% Unexplained Time Losses as % of Total Production Hours, 1.90% Total Productive Hours as % of Total Production Hours, 29.56% Minor Stoppages as % of Total Production Hours, 11.60% Breakdown Stoppages as % of Total Production Hours, 16.87% Changeover time as % of Total Production Hours, 27.20% 21

28 The downtimes for each bottling line can be divided into four major categories: 1. Non-Productive time due to bottle changeovers and water flavour changeovers 2. Non-Productive time due to breakdown stoppages and minor stoppages 3. Non-Productive time due to Rate Losses/Reduced Capacity Losses 4. Non-Productive time due to Unexplained Stoppages According to the Figure 9 shown above, the time it takes to do changeovers contribute for 27.20% (a contribution of 37.73% of the total non-operational time) of the Total Production Hours, the time spent on machine breakdowns is 16.87% and minor stoppages contributes for 11.60% of the Total Production Hours, Rate Losses/Reduced Capacity Losses due to technical processing problems contributes for 12.87% and unexplained stoppages contribute for 1.90% of the Total Production Hours. This short analysis gives a clear indication that the reasons for the underperformance of Nestlé Waters during 2007 were due to long changeover processes, machine breakdowns, minor stoppages and Rate Losses/Reduced Capacity Losses Data analysis and interpretation As stated above, four major problem areas were identified in Nestle Waters production facility namely: Long changeover processes Equipment failure and breakdowns Minor stoppages Rate losses and Reduced Capacity Different Industrial Engineering methods and techniques will be integrated and used to analyse and determine the core problems of each individual problem area stated above. These Industrial Engineering methods and techniques include: Pareto Analysis Cause and Effect Diagrams Critical analysis technique The five question analysis ( Why analysis ) P-M Analysis 22

29 Equipment failures and breakdowns As was determined previously, one of the main reasons for the poor availability of Line 1 is due to equipment failure and breakdowns. Maintenance is definitely one of the major factors contributing to the poor availability of equipment in Line 1 and it has a determinable effect on the availability. The use of a cause and effect diagram (Figure 10) assisted in determining the causes of the equipment failures and breakdowns. The Cause and Effect diagram identifies four contributing factors to any effect that is recognized in a system (Machine, Men, Method and Material). Fig. 10 Cause and Effect Diagram for Equipment failures and breakdowns Causes related to machine, men, methods and material used are discussed below: MACHINE: Nestle Waters is utilizing second hand equipment purchased from a bottling company is Russia. The majority of the equipment components are worn and experiences huge amounts of stresses. Original components are replaced with local manufactured parts that have to be customized to fit into the piece of equipment. The customized parts tend to fail faster due to the fact that they are not specifically designed for the purpose they are used for in the production line. 23

30 MEN: A huge communication gap between the operators on the floor, the maintenance personnel and the management of the company. A lack of maintenance management in the facility. Shortcoming in the training of operators to do elementary maintenance. METHODS: The need for a maintenance program and detailed maintenance planning by the management and maintenance department Utilization of the emergency repair strategy creates a feeling of fighting fires among the maintenance personnel The use of the Run Till Death (RTD) maintenance strategy on second hand machines MATERIALS: Correct consumable parts (screws, nuts, bolts, elastic bands, etc.) are not stocked and this initiates the use of inappropriate materials to fix small problems. An example is the use of cello tape or duck tape to fix leaking valves and sensors that have broken off. This project will not address the equipment failure and breakdown problem area in detail due to time limitations and the sheer size of a project that will develop a maintenance program and the installation of the maintenance program. This project will only focus on what methods could be implemented to address the equipment breakdown problems occurring in the company Minor Stoppages This part of the project will focus on the use of TPM principles and the P-M Analysis to analyse and eliminate the minor stoppages. Figure 11 was created to identify the machines which are responsible for the most downtime. The downtime of each machine is plotted on the graph (Pareto Graph) as a cumulative percentage of the total downtime. 24

31 Filler 100 head Unscrambler Shrinkwrap Palletiser Labeller Casepacker Overwrapper Capper Airconveyor Date Coder Depalletiser Slat Conveyor Bar Code Labeller Rinser Roller Conveyor Carton Gluer Stretch Wrapper Box Coder Carbonator Pallet Unwrapping Contribution Percentage Filler 100 head Unscrambler Shrinkwrap Palletiser Labeller Casepacker Overwrapper Capper Airconveyor Date Coder Depalletiser Slat Conveyor Bar Code Labeller Rinser Roller Conveyor Carton Gluer Stretch Wrapper Box Coder Carbonator Pallet Unwrapping Percentage Fig. 11 Pareto Chart based on Total Downtime of Line % % 80.00% 60.00% 40.00% 20.00% 0.00% Pareto Chart based on Total Downtime Machines It is clear from the Pareto Chart (Figure 11) that the Filler, Unscrambler and the Shrinkwrapper are the machines that give the most problems and thus needing a detail investigation. Fig. 12 Machine Contribution to Total Downtime on Line % 25.00% 20.00% 15.00% 10.00% 5.00% 0.00% Total Downtime Contribution per Machine Machines Figure 12 clearly shows that the Filler, Unscrabler and Shrinkwrapper contribute respectively 25.96%, 23.81% and 15.20% to the Total Downtime of Line 1. These three machines have a combined total contribution of 64.97% to the Total Downtime of Line 1. Though it is not an exact portrayal of the Rule it supports the fundamental concept of the rule. 25

32 Filler 100 head Unscrambler Shrinkwrap Labeller Overwrapper Capper Palletiser Casepacker Date Coder Depalletiser Slat Conveyor Airconveyor Bar Code Labeller Rinser Roller Conveyor Stretch Wrapper Carton Gluer Box Coder Carbonator Pallet Unwrapping Contribution Percentage Filler 100 head Unscrambler Shrinkwrap Labeller Overwrapper Capper Palletiser Casepacker Date Coder Depalletiser Slat Conveyor Airconveyor Bar Code Labeller Rinser Roller Conveyor Stretch Wrapper Carton Gluer Box Coder Carbonator Pallet Unwrapping Percentage Figure 13 is a more accurate and detail identification of the contribution of each machine to minor stoppage losses. Fig. 13 Pareto Chart based on Minor Stoppages for Line % % 80.00% 60.00% 40.00% 20.00% 0.00% Pareto Chart based on Minor Stoppages Machines Figure 14 indicates that the Filler has a contribution of 33.43% to the total Minor Stoppages Time, and the Unscrambler and Shrinkwrapper has a contribution of 24.71% and 9.27% respectively to the Total Minor Stoppages Time of Line 1. These three machines have a combined total contribution of 67.41% to the Total Stoppage Time of Line 1. Fig. 14 Machine Contribution to Minor Stoppages in Line % 35.00% 30.00% 25.00% 20.00% 15.00% 10.00% 5.00% 0.00% Contributions to the Minor Stoppages per Machine Machines 26

33 The results obtained from the minor stoppage losses Pareto chart (Figure 13) is closely related to the Pareto chart (Figure 11) for the total downtimes. The investigations into the causes of the high minor stoppage losses revealed that there are four significant problem areas in production line 1. These four machines contribute to the minor stoppage loss rate with the following percentages (Figure 13): 1. The Filling machine with a contribution of 33.43% to the total number of minor stoppages on line 1 2. The Bottle Unscrambler machine with a contribution of 24.71% to the total number of minor stoppages on line 1 3. The Shrinkwrapper with a contribution of 9.27% to the total number of minor stoppages on line 1 4. The Labeller with a contribution of 7.26% to the total number of minor stoppages on line 1 Fig. 15 Contributions to Minor Stoppages on Line 1 Contributions to Minor Stoppages on Line 1 Other, 25.32% Filler 100 head, 33.43% Labeller, 7.26% Shrinkwrap, 9.27% Unscrambler, 24.71% Table 3 captures all the minor stoppages experienced on Line 1 during the production year of The information illustrated in Table 3 is the data that is collected by the operators of each machine in Line 1. The time, date and reason for the stoppage are written down into logbooks which are then loaded into SAP and SAM. The reasons for the stoppage of a machine in the production line are not only due to the fact that the machine is experiencing problems, but can be caused as a result of machine malfunctions upstream or downstream. 27

34 Malfunctions that occur upstream, cause the machine to run out of bottles, water or air pressure while malfunctions that occur downstream, cause the buffer stock to meet its capacity. Examples of such occurrences during the year of 2007 on Line 1 are illustrated in Table 3. Table 3 Minor Stoppages experienced on Line 1 No. Minor Stoppages on Line 1 Minutes Filling Table out of timing Unscrambler out of timing Bottles crushed on the starwheel of the Filler Filler scroller out of timing Bottles crushed in the pockets of the Unscrambler Unknown Minor Stoppages Water shortage due to pump malfunctions Bottles falling on the Filler scroller Unscrambler guide broken Filler pistons pressure are too low Filler filling nozzles are foaming In-let to airveyor guide broken Shrinkwrapper sensor is faulty Waiting for bottles due to Airconveyor malfunction Bottle caps blocked in the hopper Bottles crushed in the Capper Bottles datecoder is not printing Airconveyor is blocked Filler is dropping the bottles Carbonation for the Filler is too low Temperature of the Shrinkwrapper is too low Waiting for temperature of Shrinkwrapper to rise Compressor tripped Blue conveyor is stuck Casepacker glue nozzles blocked Long Changeover Times There are three different changeovers on the Flavoured and Sparkling water bottling line: 1. Changing from one flavour of water to another without changing the bottle size 2. Changing the bottle size without changing the flavour of the water 3. Changing the bottle size as well as the flavour of the water to another flavour For this part of the project, Operation Analysis (the Why analysis ), TPM and SMED techniques will be utilized to improve the changeover times of the production line and the methods used during the changeovers. 28

35 Unscrambler Filler Labeler Shrinkwrapper Case Packer Time (Minutes) To assist in the understanding and description of the three different changeovers conducted on Line 1 it is helpful to visualize the sequence in which changeover tasks are conducted and the time it takes to conduct each task with the help of a Gantt chart. Interviews with each operator working on line 1 were conducted to determine each machine s estimated average changeover time in line 1. During the interviews the operators were also asked what problems they were experiencing during changeovers. The following five main problems were identified by the machine operators: The parts that needed to be changed are always missing The operators doesn t have the necessary tools for the changeovers Artisans are responsible for big parts of the changeovers The machine settings are done by the artisans Poor organization and communication between team members Figure 16 shows the estimated average changeover times of the five most critical machines during each of the three different changeovers that can occur in line 1. Fig. 16 The changeover times on line 1 Changeover times on line Flavour Changeover, No Bottle Changeover Bottle Changeover, No Flavour Changeover Flavour Changeover and Bottle Changeover Machines The data that is illustrated in Figure 16 clearly shows that the two biggest concerns in line 1 are the filling machine and the unscrambler. During the first type of changeover on line 1 (flavour changeover, no bottle changeover), it isn t necessary to do any changeovers on the unscrambler, the shrinkwrapper and the case packer because these machines will not be affected by the flavour changeover (as illustrated in Figure 16). 29

36 The unscrambler, the shrinkwrapper and the case packer will need component changeover when the bottle sizes are changed in the line. The analysis of the three types of changeovers will focus on the changeover times of the filling machine and the unscrambler due to the fact that they are the biggest concern for the company. Operation Analysis techniques, the Why Analysis (Figure 2) and the Critical Analysis (Figure 3) should be used to determine why the changeovers are taking too long, what tasks needs to be done, why they need to be done, what tools are used, where the tools are allocated, when the tasks should be done, how the tasks are being executed, who executes these tasks, etc Flavour change without bottle size change The flavour changeover without changing the bottle size is the easiest and quickest changeover of the three changeovers on line 1. The components of the machines utilized in line 1 don t have to be replaced with the changeover due to the fact that only the flavour of the water is changed and not the size of the bottle. Time studies of the flavour changeover were done and are represented in Figure 17 as a Gantt chart. Fig. 17 Gantt chart representing the changeover tasks of the filler Gantt Chart for the changeover tasks of the filler Screwing CIP cups onto filler points Removing excess material, caps & water from Filler Preparing Filler for CIP CIP Mixing the next flavour syrup Transporting the bottle caps Filling the hopper with caps Preparing the Filler for the flush Flushing the Filler Preparing the Filler for new flavour water Correcting the Filler programming Filling the tanks with syrup Removing CIP cups Test run Time (Minutes) 30

37 Figure 17 shows that there are two immediate problem areas that can be identified with a quick investigation. The first concern is the time it takes to perform the CIP on the filling system. CIP is the cleaning of the filling system from excess syrup and flavoured water to ensure that the next flavour doesn t have any traces of the previous flavour that was bottled. This ensures that pure flavoured water will be bottled. The CIP is expected to have a duration period of 30 minutes but during the time studies of the changeovers it was determined that the CIP has an actual duration of 45 to 50 minutes. No explanation could be found for the longer duration of the CIP. It is suspected that it is due to communication gaps between the operators of the Filler and the operators that carry out the CIP. The second concern is the fact that the changeover is not planned before it is carried out. The Gantt chart shown in Figure 17 clearly shows that a lot of the activities are completed in sequence (one after the other). These activities mentioned in the Gantt chart include internal and external tasks. A closer study with the help of the SMED methodology and the critical analysis technique will identify which activities can be done simultaneously and which activities has to be done in sequence. There are no changeover activities on the Unscrambler due to the fact that only the flavour of the water is changed and not the size of the bottles Bottle changeover without flavour changeover The bottle changeover without changing the flavour of the water is more complex than the previous changeover due to the fact that the components of the machines utilized in line 1 has to be removed and replaced with the needed components to accommodate the new bottle size. Time studies that were done during this type of changeover revealed the data represented in Figure 18 as a Gantt chart. Figure 18 illustrates that all the activities that are done during the bottle changeover without the flavour change, are done the one after the other. The reason for this is that there is only one operator per machine in the filling line that has to carry out the changeover activities on his/her machine. The operator begins at a point and work his way through all the activities that needs to be done. 31

38 Fig. 18 Gantt chart representing the changeover tasks for the Filler Lift/lower buffer tank height Lift/lower capper head height Lift/lower shute height Lift/lower top plate height Find and transport the components that need to be changed Find the tools needed for the changeover Wait for Artisan to assist machine operator Remove and Install Infeed Scroll (Left) Remove and Install Infeed Scroll (Right) Remove and Install Infeed Guide (Left) Remove and Install Infeed Guide (Right) Remove and Install bottle clamps Remove and Install bottle guide Remove and Install infeed starwheel upper Remove and Install infeed starwheel lower Remove and Install intermediate bottle guide Remove and Install intermediate starwheel upper Remove and Install intermediate starwheel lower Remove and Install conveyor bottle guide infeed Remove and Install conveyor bottle guide outfeed Remove and Install upper cap starwheel (x2) Remove and Install lower cap starwheel (x2) Remove and Install Block Remove and Install outfeed guide Remove and Install reject starwheel (x2) Remove and Install reject bottle guide Remove and Install outfeed guide (left) Remove and Install outfeed guide (right) Remove and Install cap shute guide Remove and Install cap guide outfeed Change settings on the programming with the assistance of the artisan Trial run Correct problems Gantt Chart for the changeover tasks of the filler Time (Minutes) 32

39 The operator of the filling machine adjusts the buffer tank height, the capper head height, the cap-chute height and the top-plate height to fit the requirements to accommodate the new bottle size (Figure 18). After minor adjustments are made to the capping machine (which forms part of the filling machine), the operator receives his/her components required for the changeover at the maintenance stores. All the components/parts of the facility are stored in the maintenance stores. The operator has to transport these components from the maintenance stores (which are situated more or less 35 meters outside the factory building) to the filling machine. The distance needed to be travelled from the filling machine to the maintenance stores and back to collect the filling machine components is about 110 meters. The parts are transported by hand and with a forklift truck. The transportation of the parts increases the risk of damaging the parts that are required for the changeover. During the collection and transportation of the parts to the filling machine, the operator has to receive the tools needed for the changeover at the maintenance stores. There are only six sets of general tools that can be used by the operators of the machines. These sets of tools are stored in the maintenance stores outside the factory building. One of the major problems that the operators mentioned is that there is a shortage of tools. The operators have to wait for a set of tools if all six the tool sets already have been taken for other purposes by other operators. During the changeover all six tool sets have to be used by the machine operators, but most of the time other employees of the company uses some of the tool sets for minor maintenance work in the facility and this results in a shortage of tools during the changeovers. When all parts and tools have been collected by the operator, the operator has to wait for an artisan to assist him/her in the changeover activities. Nestle Waters currently employs five artisans that can assist the operators with the changeover activities and correct other maintenance problems occurring in the plant. Just as in the case of a shortage of tools during the changeover, there is also a shortage in artisans. The operators have to wait most of the times for an artisan to assist them in the changeover activities because the artisans are busy with other smaller maintenance problems in the facility or they are assisting other operators during the changeover. The only way that the changeover activities can commence is when an artisan can assist the operator of the machine. The operator of the machine and the artisan are the only people that carry out the changeover activities on the machine, which is why all the other activities are done the one after the other. There aren t enough hands to do the work quicker. 33

40 Fig. 19 Gantt chart representing the changeover tasks for the Unscrambler Gantt Chart for the changeover tasks of the Unscrambler Stop the unscrambler Locate the parts that need to be changed Transport the pockets to the unscrambler Find the tools needed for the changeover Wait for Artisan to assist machine operator Remove the 'old pockets' Install the 'new pockets' Adjust pocket openings Change settings on the programming with the Trial run Correct problems Time (Minutes) Figure 19 illustrates the changeover activities that were captured during the bottle changeover on the Unscrambler. Production time is lost during the changeover due to the transportation of the parts and the physical change of the components on the Unscrambler. As mentioned above, there is only one operator per machine on line 1 that has to do the changeovers. That is the reason why all the changeover activities are done one after the other and the operator has to wait for an artisan to assist him/her with some of the activities. The physical changeover of the parts takes on average 2.7 hours due to the size and weight of the pockets. Figure 20 illustrates the dimensions and weight of each pocket that has to be removed and installed with each changeover. The pocket has a trapezoid shape that is hollow to guide the bottles into the air conveyor. The pockets dimensions and weight, due to the fact that it is made out of steel, makes it very difficult to transport and handle. After the new pockets have been installed, the pocket openings/inlets at the top of the Unscrambler have to be adjusted to fit the new bottle size. 34

41 Fig. 20 Dimensions of the Unscrambler pockets Flavour change and bottle change The bottle and flavour changeover is the longest changeover and is the most complex of the three different changeovers. During this changeover the components of the machine utilized in line 1 has to be removed and replaced with the needed components to accommodate the new bottle size and the flavour of the water has to be changed as well. Theoretically this changeover is the combination of the first two changeovers. Figure 21 clearly shows that the bottle and flavour changeover is more or less a combination of the previous two changeovers when the changeover activities that are performed and the sequence they are performed in are considered. 35

42 Fig. 21 Gantt chart representing the changeover tasks for the Filler Gantt Chart for the changeover tasks of the Filler Screwing CIP cups onto filler points Removing excess material, caps & water from Filler Preparing Filler for CIP Lift/lower buffer tank height Lift/lower capper head height Lift/lower shute height Lift/lower top plate height CIP Mixing the next flavour syrup Preparing the Filler for the flush Flushing the Filler Find and transport the components that need to be changed Find the tools needed for the changeover Wait for Artisan to assist machine operator Remove and Install Infeed Scroll (Left) Remove and Install Infeed Scroll (Right) Remove and Install Infeed Guide (Left) Remove and Install Infeed Guide (Right) Removing CIP cups Remove and Install bottle clamps Remove and Install bottle guide Remove and Install infeed starwheel upper Remove and Install infeed starwheel lower Remove and Install intermediate bottle guide Remove and Install intermediate starwheel upper Remove and Install intermediate starwheel lower Remove and Install conveyor bottle guide infeed Remove and Install conveyor bottle guide outfeed Remove and Install upper cap starwheel (x2) Remove and Install lower cap starwheel (x2) Remove and Install Block Remove and Install outfeed guide Remove and Install reject starwheel (x2) Remove and Install reject bottle guide Remove and Install outfeed guide (left) Remove and Install outfeed guide (right) Remove and Install cap shute guide Remove and Install cap guide outfeed Transporting the bottle caps Filling the hopper with caps Preparing the Filler for new flavour water Change settings on the programming with the assistance of the artisan Filling the tanks with syrup Trial run Correct problems Time (Minutes) 36

43 The problems that are experienced during the bottle and flavour changeover are exactly the same as the problems mentioned in the previous two types of changeovers. The only difference is that the order in which the changeover activities are done are different. Figure 22 is the changeover activities that are performed on the Unscrambler during the bottle and flavour change. The changeover activities are exactly the same as for the previous mentioned type of changeover (bottle changeover, not flavour changeover) because of the fact that the Unscrambler has nothing to do with the flavour of the water but only with the size of the bottle utilized. Fig. 22 Gantt chart representing the changeover tasks for the Unscrambler Gantt Chart for the changeover tasks of the unscrambler Stop the unscrambler Locate the parts that need to be changed Transport the pockets to the unscrambler Find the tools needed for the changeover Wait for Artisan to assist machine operator Remove the 'old pockets' Install the 'new pockets' Adjust pocket openings Change settings on the programming with the Trial run Correct problems Time (Minutes) The analysis of these three types of changeovers on line 1 clearly highlights the same problems that the operators identified. These problems include: Poor planning and communication between operators and team members before and during changeovers Tool shortages during changeovers Parts/components needed for changeovers are missing Transportation of parts/components over long distances Lack of trained operators Shortage of employees 37

44 One of the main reasons why the changeovers take on average six hours, is the fact that the changeover activities have never been classified into internal and external tasks to identify which activities can be done simultaneously or which activities has to be done by stopping the line. The changeover methods have never been revised and simplified. The SMED methodology and critical analysis techniques will be utilised to decrease the changeover times Rate Losses/Reduced Capacity Losses The reduced capacity losses are defined as the difference between the rated capacity of the equipment and the capacity at which it is operating (Wireman 1991). As stated in section , the capacity of the equipment used is reduced by two main reasons: speed of the equipment and the output volume of the equipment. The equipment utilized at Nestle Waters for production purposes are second hand equipment procured from a bottling plant in Russia. The age of the equipment is unknown but it is estimated at about 15 years old. Table 4 Original design capacities of machines utilized in Line 1 Bottles/Hour 500 ml 1.5 litre Filler Unscrambler Shrinkwrapper Labeller Theoretically the shrink wrapper is the bottleneck of the system when it is running at full design capacity, but during the past years a lot of alterations and customized improvements were made on these machines that increased and reduced these design capacities. Time studies of the system revealed that the filling machine is the new bottleneck of the system. The filling machine struggles to produce more than ml bottles and litre bottles. Every time the filling machine is pushed over these limits, minor stoppages increases drastically. The production team decided to rather keep the production rate of the filling machine beneath ml bottles and litre bottles to prevent the increase in minor stoppages on the filler. 38

45 The filling machine experiences the following stoppages when the machine is pushed over these limits: Bottles get crushed in the machine The filler looses its timing Bottles aren t filled properly Bottle caps aren t applied and tightened according to specification The Reduced Capacity Losses are closely related to the Capacity Reduction Breakdowns discussed in section Capacity reduction breakdowns are caused by the neglect of chronic equipment problems that occur in the production lines. According to Wireman (1991), a typical example would be equipment that produces a defective product when operating at any rate over 80% of design speed. Instead of taking the time and effort necessary to correct the problem, the organization will issue a memo stating not to run the equipment over 80% of design speed. This results in a 20% reduction in equipment capacity. This is exactly what is happening at Nestle Waters. Nestle Waters are accepting these chronic problems and in return decreasing the production rates of the equipment each time the equipment shows problems keeping up with the desired production speed. The rule to remember in this area is to not accept anything less than capacity rated performance from any equipment. If this rule is followed, all necessary steps will be taken to correct minor problems before they become major problems (Wireman 1991). 39

46 8. Problem Solving The aim of this project is to improve the productivity of the Sparkling and Flavoured Water Bottling Line at Nestle Waters. All relevant data and information relating to the four problem areas mentioned were given and the problem solving phase can begin. This section will firstly focus on the breakdowns, minor stoppages and rate losses experienced in Line 1 and then the focus will turn to improving the long changeover times and general productivity improvements during changeovers Total Productivity Maintenance (TPM) As mentioned in section 6.2.2, Cigolini and Rossi (2004) states that the TPM approach is a methodological pattern to increase automated lines productivity by minimizing production losses. TPM is used to maximize overall machine productivity in a company, to implement maintenance programs and to encourage the involvement of the company functions. According to Wireman (1991), the goal of TPM can be divided into the following five segments: 1. Ensuring equipment capacity ensuring equipment capacity signifies that the equipment utilized in the company performs to specifications. The equipment operates at their designed speeds, they produce at their design rates, and this in turn results in quality products at these speeds and production rates. 2. Implementing maintenance programs implementing a maintenance program for the life cycle of the equipment utilized in the company is the equivalent to the preventive and predictive maintenance programs that companies use to maintain their equipment. This maintenance program has a basic difference from traditional maintenance techniques: the maintenance program changes as the equipment changes. Each piece of equipment needs different amounts of maintenance activities as the piece of equipment ages. Preventive/predictive maintenance programs accommodate these changing needs of the equipment utilized. This program involves all employees, from the operator to the upper management. 3. Support from all departments requiring the support of all departments within the company that is involved in the use of the equipment utilized in the company will guarantee the full cooperation and understanding of the affected departments. Good support can help with standardization, maintenance, reduce downtime and optimize inventory levels. 40

47 4. Solicit input from all employees soliciting input from employees at all levels of the company provides them with the ability and opportunity to make a contribution to the process. A suggestion program is one of the commonly used programs used by companies. The suggestion program should include a management that is open and available to listen and to give consideration to employee suggestions. 5. Continuous Improvement the development of the combined teams for continuous improvement begins with the previous step. With a management that is open for new ideas from employees, continuous improvement will flourish in the company. Continuous improvement teams can be formed by areas, departments, lines, process, or equipment and will involve operators, maintenance, and management personnel. A well-established and well-defined TPM program will have the following advantages for any company: Increased production capacity and productivity Highest quality products Lower production costs Decrease in breakdown losses Decrease in setup and adjustment losses Decrease in idling and minor stoppage losses Decrease in reduced capacity losses Decrease in start-up/restart losses It is clear from the data and information gathered on the problems experienced at Nestle Waters that their main concerns are the breakdown of equipment, long setup and adjustment times, minor stoppages and reduced capacity losses. From the research done for this project it is clear that TPM is a program that is specifically developed for situations such as the one Nestle Waters is finding them at the moment. TPM was developed and tested to cover and deal with all of these problems mentioned and it is a suitable and tested solution for the problems experienced at Nestle Waters. 41

48 The purpose of this project is not to physically implement TPM (due to the sheer size of the implementation process of TPM), but rather to use some of the TPM techniques and other industrial engineering methods mentioned to solve the individual problems that were identified at Nestle Waters. TPM will form the basis of all the solutions and problem solving techniques suggested in this project, while other industrial engineering methods and techniques will be used as an additional enhancement to the TPM techniques used Equipment Failures and Breakdowns This section of the project will not discuss the equipment failure and breakdown solutions in detail, but rather make suggestions on what methods and actions could be implemented to assist in the prevention of these breakdowns occurring in Line 1. TPM uses the zero breakdown concept to eliminate capacity reduction and capacity loss breakdowns. At the core of the zero breakdown concept is the preventive/predictive maintenance program. Preventive/predictive maintenance programs are used to increase equipment availability and reliability in the company, but most importantly, they reduce the amount of reactive work that have to be done by the maintenance department and this results in a proactive maintenance department. Fig. 23 Preventive Maintenance Techniques Figure 23 is an illustration of the five different types of preventive maintenance techniques that should be performed to accomplish zero breakdowns Routines, Lubrication, Cleaning, Inspections This type of preventive maintenance is the most basic and most important technique of preventive maintenance. It is also the basis of the development and implementation of a TPM program. These basic tasks can be done by the operators of the equipment on the bottling line. The few materials and tools required to perform these tasks have to be stored in a toolbox at the machine that the operator is operating. 42

49 Each toolbox has to be allocated to a specific operator and they will have to take full responsibility for the toolbox and the tools in the toolbox to prevent tools being stolen. On each shift, the toolbox has to be signed in and out in a logbook by the operator responsible for that specific toolbox. If there are tools missing in the toolbox, the operator that is responsible for that toolbox will have to face the consequences if he doesn t have a clear explanation for the disappearance of tools. Fig. 24 Toolbox for each operator The routines that are required to be done by the operators include small inspections and adjustments performed on the equipment before and after a changeover, or shutdown/startup of equipment. Four basic routine tasks were identified which the operators can perform: Tightening Lubricating Cleaning Inspections Tightening prevents looseness of any parts on the equipment, which in turn prevents vibrations and accelerated wear on the machines in the line. Lubrication of equipment should also be done by the operators. The lubrication point and the lubricant should be colour coded to eliminate mistakes about what lubricant goes to what lubrication point on the machine. It is also very important to specify how much lubricant goes in each lubrication point, because in many cases it is as bad or worse to pour in too much lubricant than too little. 43

50 Fig. 25 Colour coded lubrication points Cleaning is one of the most beneficial tasks for a piece of equipment according to Wireman (1991) and Nakajima (1988). While the operator is wiping of his/her machine, the operator will spot many small problems before they have developed into larger problems. When the operator spots a problem on his/her machine, he/she must write a work request for the maintenance department to correct the problem before it becomes a major problem and after the problem has been corrected the maintenance department must comment on the work request. This small system will prevent equipment breakdowns and improve communication between the different departments. Inspection is closely related to the cleaning of the equipment. performed simultaneously. These two actions are All operators on the production floor will have to receive training in the tasks they have to perform and what are expected from them. The training has to be in accordance with the standard practices and procedures of Nestle Waters and include all related safety instructions and standards Proactive Replacements and Scheduled Refurbishing According to Wireman (1991), proactive replacements involves taking a piece of equipment off the bottling line and repairing it, replacing all worn parts on that piece of equipment, and putting the piece of equipment back on the production line. 44

51 The overhauled piece of equipment will then be operational for an extended period of time without any maintenance related downtime. This technique targets components that are approaching the end of their life cycle. This event must be carefully planned that it would have a minimal impact on the production schedule of the bottling line. These actions should preferably take place in conjunction with routine shutdowns and other maintenance activities that need to be done. An initial increase in the parts costs will be experienced because this program is usually started when most equipment is in poor condition such as in the case of Nestle Waters. The parts costs should become relatively fixed as the equipment components are replaced Predictive Maintenance Predictive maintenance is the measurement of the physical parameters of a machine to detect, analyze and correct problems that occur on the machine before capacity reductions or losses occur. Predictive maintenance is a maintenance program where the physical maintenance actions are performed when the machine requires it (predictive maintenance is not planned). The key to a successful predictive maintenance program is to identify physical parameters that will show the tendency of failures on equipment. When a parameter for a certain machine is established, lower and upper limits for the parameter should be set. The current conditions of the parameter should be measured and compared to the limits that were set. When the current conditions exceed the upper limit of the parameter, maintenance services are required on the machine. The most common parameters in the industry are illustrated in Table 5. Table 5 Parameters used for Predictive Maintenance Parameter Discription 1. Vibration Analysis Monitoring the frequency of the vibration in rotating equipment 2. Shock-Puls Analysis Detection of mechanical shock pulses caused by rotating equipment 3. Temperature Analysis Utilization of thermographic cameras or infrared scanners to detect and monitor heat exposure of equipment 4. Oil Analysis Analysis of the oil structure and wear particles in the oil to determine the amount of wear on the piece of equipment 5. Resistance Analysis Tests electricity components to ensure that they are not shorted out of damaged 45

52 Condition-Based Maintenance Condition-based maintenance and predictive maintenance are very similar to each other. The only difference between the two programs is that employees don t use hand-held devices to take measurements. The measurements are taken by permanently mounted sensors on the machine, and send the signal or information to a control room. All the readings can be remotely checked, monitored and integrated into a control system or maintenance system. The programmable logic controller enables the employees to take realtime measurements of the parameters. Maintenance technicians can then monitor live readings and actually perform troubleshooting Reliability Engineering Reliability engineering is used to provide solutions to problems that cannot be addressed by the above mentioned techniques. Equipment availability can be ensured by the utilization of redesigns, retrofits, and mathematical models. Through the implementation of the various preventive maintenance techniques discussed briefly, Nestle Waters can reduce their breakdown frequencies and increase the machine life and productivity of Line 1. Great results have been achieved by various companies over the world with the implementation of TPM and related maintenance programs Rate Losses/Reduced Capacity Losses The Rate Losses experienced on Line 1 are closely related to the Capacity Reduction Breakdowns discussed in section and the suggested solution to counter these losses will be exactly the same as discussed in section Rate Losses and Capacity Reduction Breakdowns are both caused by the lack of equipment maintenance on old and worn equipment. The preventive maintenance program, which forms part of the TPM strategy, incorporates the improvement of the Rate Losses experienced on Line 1. 46

53 8.2. Phenomenon-Mechanism Analysis (P-M Analysis) TPM procedures developed by the Japan Institute of Plant Maintenance deals with breakdowns, set-ups/changeovers, speed losses, defective quality, yield losses and minor stoppages. The Japan Institute of Plant Maintenance developed the Phenomenon- Mechanism analysis in conjunction with TPM to assist and enrich the techniques utilized by TPM. Cigolini and Rossi (2004) had great successes in their case study where they utilized the P-M analysis to establish and eliminate the causes of minor stoppages in a tissue converting line. P-M analysis allows all the potential causes for minor stoppages to be identified and in turn minimizing the minor stoppages experienced on the line and improving the productivity of the production line Step 1: Clarify the Phenomenon The first step of the P-M analysis is to define and categorize the abnormal phenomenon experienced in Line 1. For this project the phenomenon will be the problems that are causing the minor stoppages on Line 1. The data and information gathering section revealed that minor stoppages contribute for 11.6% of the total production time available per year. Further investigation also revealed that the filling machine and the Unscrambler are the biggest problems concerning minor stoppages on Line 1. The Filler and Unscrambler contribute for 33.43% and 24.71% respectively to the total minor stoppages on Line 1 (Figure 15). 47

54 Step 2: Conduct a physical analysis This step involves describing the phenomenon in physical terms, how the machine or process conditions are changing in relation to each other to produce defects or failures The Filler Table 3 in section 7.3.2, shows the most common and time consuming minor stoppages recorded by the operators on Line 1. The minor stoppages experienced on the Filler are as follows: 1. The filling table is out of timing 2. Bottles are being crushed in the star wheel of the Filler 3. The Filler scrollers are out of timing 4. Bottles falling on the Filler scroller 5. Filler pistons pressure are too low 6. Filler filling nozzles are foaming 7. Bottles crushed in the Capper Figure 26 illustrates where these seven mentioned minor stoppages is occurring on the Filling machine. Fig. 26 Filling Machine 4 1,5, The description of the normal Filler operations for each of the affected areas identified that the minor stoppages occur in is described in Table 6. 48

55 Table 6 Filler operations physical descriptions Minor Stoppage on the Filler Physical Description 1. Filling table out of timing The bottles are fed to the filling table by the in-feed star wheel. The bottle is pushed over the bottle control bottom plate to support the bottle and the bottle neck is then grabbed by the bottle clamp to hold the bottle steady. The bottle control pushes the bottle neck over the filling nozzle of the filling table that is situated 10mm above the bottle opening and the bottle is filled with flavoured water. 2. Bottles crushed in Filler star wheel The bottles are fed to the in-feed star wheel by the filler scrollers. The bottles are guided by the star wheel with the help of the bottle-guides into the filling table. When the bottles are filled they are guided out of the filling table by the out-feed star wheel. 3. Filler scrollers out of timing The bottles are fed to the filler scrollers by the out-feed star wheel of the rinsing machine. The bottles are conveyed to the in-feed star wheel of the filling table. 4. Bottles falling on the Filler scrollers The bottles are fed to the filler scrollers by the out-feed star wheel of the rinsing machine. The bottles are conveyed to the in-feed star wheel of the filling table. 5. Filler piston pressures are too low When the bottles are firmly gripped by the bottle controller, the bottle neck is pushed over the filling nozzle with the help of an air piston situated at the bottom of the bottle control. 6. Filler filling nozzles are foaming When the bottles are firmly gripped by the bottle controller and the bottle neck is pushed over the filling nozzle by the air piston, the filling table fills the bottle with flavoured carbonated water through the filling nozzle. 7. Bottles crushed in the Capper The bottles enter the capping machine via the out-feed star wheel of the filling table. Caps are put on top of the bottle neck and screwed onto the bottle by the capping machine while the bottles are guided by the capping star wheel. 49

56 The Unscrambler Table 3 in section 7.3.2, lists, among other minor stoppages on Line 1, the minor stoppages that are occurring most frequently on the Unscrambler. The minor stoppages experienced on the Unscrambler are as follows: 1. The Unscrambler is out of timing 2. The bottles get crushed in the pockets of the Unscrambler 3. The Unscrambler guide is broken Figure 27 is an illustration of where these mentioned minor stoppages is occurring on the Unscrambler. Fig. 27 Bottle Unscrambler Table 7 is an elaboration on the standard operating procedures of the identified areas where minor stoppages occur. 50

57 Table 7 Unscrambler operations physical description Minor Stoppage on the Unscrambler Physical Description 1. Unscrambler out of timing The bottles are thrown into the gravitation dish where the bottles fall into slots. The bottles falls through the slots into the pockets as the pockets rotate underneath the stationary slots. 2. Bottles are crushed in the Unscrabler pockets When the bottles falls through the stationary top slots and into the rotating pockets, the pockets are emptied when it passes over the stationary bottom slot which feeds the air conveyor. 3. Unscrabler guide is broken The bottles fall out of the pockets when the rotating pockets pass over the stationary bottom slot which feeds the air conveyor with bottles. The bottles are guided by a steel guide into the conveyor Step 3: Causal Factors of the Minor Stoppages Step 3 consists of identifying the conditions that is necessary for the occurrence of the phenomenon The Filler Table 8 discusses the conditions and events that are experienced during each minor stoppage that was identified on the Filler. 51

58 Table 8 Minor Stoppages on the Filler Minor Stoppage on the Filler Minor Stoppage description 1. Filling table out of timing Each time the Filler has to be stopped and restarted due to stoppages on Line 1, part of the programming of the Filler has to be reset and reprogrammed by the operator. The machine starts at low production rates and speeds up to the programmed production rate. The bottles aren't aligned well enough that the bottle clamp can grip the bottle neck properly. The bottles are then crushed or damaged by the bottle control. 2. Bottles crushed in Filler star wheel When the bottles come into the in-feed and out-feed star wheels of the filling table, the bottles get crushed between the star wheel and the bottle guide. 3. Filler scrollers out of timing The bottles get crushed and damaged as they go through the scrollers to the fillers. This creates congestion and the Filler has to be stopped momentarily to clear the congested scrollers. 4. Bottles falling on the Filler scrollers This minor stoppage is very similar to the previously mentioned stoppage. The bottles fall over and get damaged as they go through the scrollers to the fillers. This creates congestion and the Filler has to be stopped momentarily to clear the congested scrollers. 5. Filler piston pressures are too low When the bottle control pushes the empty bottle against the filling nozzle, the filling nozzle doesn't go deep enough into the bottle opening. This causes that bottles are not filled properly and that huge amounts of water is spilled. 6. Filler filling nozzles are foaming When the bottle is filled with flavoured carbonated water, the flavoured water 'boils' over. This results in bottles that are not filled properly. 7. Bottles crushed in the Capper The filled bottles are crushed and damaged in the Capping machine while the caps of the bottles are screwed on the bottles by the Capping machine. 52

59 The Unscrambler Table 9 discusses the conditions and events briefly that are experienced during each minor stoppage that was identified on the Unscrambler. Table 9 Minor stoppages on the Unscrambler Minor Stoppage on the Unscrambler Minor Stoppage description 1. Unscrambler out of timing Each time the Unscrambler has to be restarted due to stoppages on Line 1, the machine starts at low production rates and speeds up to the programmed production rate. The stationary top slots of the Unscrambler have a hatch that opens when the pocket passes underneath. After restarting the Unscrambler, the timing of the hatch is out and this causes the bottles not to fall into the pockets. 2. Bottles are crushed in the Unscrabler pockets When the bottles fall into the rotating pockets, the pockets are emptied when they pass over the stationary bottom slot. The bottles get crushed when the pocket is mechanically tilted to be emptied into the stationary bottom slot. 3. Unscrabler guide is broken The bottles get crushed when they are guided into the air conveyor by the steel bottle guide. 53

60 Step 4: Cause and Effect Analysis Potential causes and effect relationships can be obtained by investigating the relationships between men, machine, materials and methods by utilizing the Cause and Effect Analysis. The root causes of the minor stoppages on the Filler and the Unscrambler were combined and illustrated in Figure 28. Fig. 28 Cause and Effect Diagram for the minor stoppages on the Filler The Filler The minor stoppages experienced on the Filler is caused mainly due to the utilization of old and worn equipment, old and worn components, the lack of proper maintenance on the equipment, the shortage of innovative and standardized operating procedures, operator negligence and the need for properly trained operators. Table 10 discusses the causes of the seven minor stoppages on the Filler in more detail. Minor stoppages involving the scrollers and the star wheels are caused by the utilization of old and worn components. These components have developed a tolerance on their axis from the wear and tear these components have endured over the years. These tolerances creates slip on moving parts and creates a looseness when the components are fitted together. When the components are replaced during a changeover, the operators have no idea on how tight the nuts should be tightened and where the exact position of the component is before tightening them. There is no suggestion of measurements and component positions. It is done by feeling. Minor stoppages are then created by parts that were not fitted properly. 54

61 Table 10 Causes of the minor stoppages on the Filler Minor Stoppage on the Filler Causes of minor stoppages 1. Filling table out of timing 1. The operators overrule the programming after each start-up and increase the production rate of the filling table manually. This abnormal acceleration causes the filling table to 'loose' its timing. 2. Due to the fact that the machines are old and worn, the components develop a tolerance and this tolerance creates slip which contributes to the filling table 'loosing' its timing. 3. When the filling table 'looses' its timing, the bottle control and the bottle isn't centred and causes bottles to be crushed by the bottle control. 2. Bottles crushed in Filler star wheel 1. The bottles are crushed in the filler star wheels after every changeover. 2. During the changeover the star wheels aren't adjusted correctly and this creates a tolerance between the guide and the star wheel. The tolerance causes that the bottles are crushed due to the varying distances between the bottle guide and the star wheel. 3. The tolerances can also be created by worn equipment. 3. Filler scrollers out of timing 1. The bottles are crushed in the filler scrollers after changeovers and during long production runs. 2. During the changeover the scrollers aren't set in place correctly and this creates a tolerance between the two scrollers. The tolerance causes that the bottles are crushed due to the varying distances between the two scrollers. 3. During long production runs the scrollers vibrate and this vibration also creates tolerances between the two scrollers. 4. The tolerances between the two scrollers are also created by worn equipment. 55

62 4. Bottles falling on the Filler scrollers 1. The bottles fall over between the two scrollers after changeovers and during long production runs. 2. During the changeover the scrollers aren't set in place correctly and this creates a tolerance between the two scrollers. The tolerance causes that the bottles fall over between the two scrollers due to the wider space between the two scrollers. 3. During long production runs the scrollers vibrate and this vibration also creates the widening of the space between the two scrollers. 4. The tolerances between the two scrollers are also created by worn equipment. 5. Filler piston pressures are too low 1. The drop in the piston pressure is caused by a leakage in the compressed air system. 2. The cause of the leakages in the compressed air system is caused by operator negligence and worn equipment. 6. Filler filling nozzles are foaming 1. When the flavoured carbonated water is pored into the bottle, the flavoured water 'boils' over. This reaction is caused by too high pressures in the nozzle and the water temperature that is too high. 2. The reaction is mainly caused by operator negligence. 7. Bottles crushed in the Capper 1. The bottles are crushed in the Capper star wheel after changeovers has been done. 2. During the changeover the star wheel is not installed and adjusted correctly and this creates a tolerance between the guide and the star wheel. The tolerance causes that the bottles are crushed due to the varying distances between the bottle guide and the star wheel. 3. The tolerances is also be created by worn equipment. 56

63 The Unscrambler Table 11 discusses the causes of the identified minor stoppages on the Unscrambler in more detail. Table 11 Causes of the minor stoppages on the Unscrambler Minor Stoppage on the Unscrambler Minor Stoppage description 1. Unscrambler out of timing 1. The operators overrule the programming after each start-up and increase the production rate of the Unscrambler manually. This abnormal acceleration causes the Unscrambler to 'loose' its timing. 2. Due to the fact that the machines are old and worn, the components develop a tolerance and this tolerance creates slip which contributes to the Unscrambler 'loosing' its timing. 3. When the Unscrambler 'looses' its timing, the stationary top slot hatches doesn't open correctly and the bottles does not fall into the pockets. 2. Bottles are crushed in the Unscrabler pockets 1. The bottles are crushed between the pockets and the stationary lower slot. The rotating pockets are mechanically tilted as they pass over the slot. 2. This is caused by worn equipment that developed tolerances on their axis. 3. The pockets are deformed and damaged by the transportation from and to the maintenance stores. This creates an imbalance and 'scewness' of the pockets which in turn crushes the bottles when being emptied. 3. Unscrabler guide is broken 1. The Unscrambler experiences huge amounts of vibration. The bottle guide is not strong enough and tightened hard enough to withstand the vibrations of the Unscrambler and the pressure of the bottles pressing against it. The major concern related to the minor stoppages experienced on the Unscrabler is the utilization of old and worn components and the need for standard operating procedures and methods. Two different machines were examined to determine the causes of the stoppages experienced on them and in both situations the same causes were established as illustrated in the Cause and Effect diagram (Figure 28). 57

64 Step 5: Propose and make improvements The fifth step involves the identification of effective methods to counteract the causes of the minor stoppages occurring on the production line. The methods and improvements that are proposed and implemented will in return decrease and eliminate the minor stoppages The Filler The suggested improvements to decrease and eliminate the minor stoppages on the Filler are tabulated in Table 12. Table 12 Minor stoppage improvements on the Filler Minor Stoppage on the Filler Minor stoppage improvements 1. Filling table out of timing 1. Standard operating procedures should be documented and the operators have to be trained to operate the equipment according to these standard operating procedures. This will prevent the operators from operating the equipment manually. 2. A well-established maintenance program, as stated in section 8.1.1, will prevent worn equipment that causes slip in moving components. 3. The maintenance program will ensure that the filling table keeps its timing by decreasing the slip on moving components. 2. Bottles crushed in Filler star wheel 1. The use of functional clamps and visible set point-marks on the equipment will ensure that the star wheel is mounted and installed the right way, the first time (discussed in detail in section ). This will in turn ensure that the bottles aren't crushed between the star wheel and the bottle guide. 2. A well-established maintenance program, as stated in section 8.1.1, will prevent the wear and tear on equipment and in turn decrease the tolerance on the star wheel. 3. Filler scrollers out of timing 1. The use of functional clamps, visible set point-marks and fixed numerical scales on the equipment will ensure that the scrollers are set in place the right way, the first time (discussed in detail in section ). This will ensure that the bottles aren't crushed due to varying distances between the scrollers. 2. The functional clamps that replace the ordinary bolts on the scrollers will ensure that the scrollers won't loosen due to vibrations. 3. A well-established maintenance program, as stated in section 8.1.1, will prevent the wear and tear on equipment and in turn decrease the tolerances on the scrollers. 58

65 4. Bottles falling on the Filler scrollers 5. Filler piston pressures are too low 1. The use of functional clamps, visible set point-marks and fixed numerical scales on the equipment will ensure that the scrollers are set in place the right way, the first time (discussed in detail in section ). This will ensure that the bottles aren't crushed due to varying distances between the scrollers. 2. The functional clamps that replace the ordinary bolts on the scrollers will ensure that the scrollers won't loosen due to vibrations. 3. A well-established maintenance program, as stated in section 8.1.1, will prevent the wear and tear on equipment and in turn decrease the tolerances on the scrollers. 1. The negligence of the operators can be corrected by standard operating procedures for each machine in the plant. This will ensure that the operators will not forget an air pressure valve open when operating on the equipment. 2. The replacement of the old compressed air lines with new durable lines will prevent unnecessary leakages. 6. Filler filling nozzles are foaming 1. Standard operating procedures should be documented and the operators have to be trained to operate the equipment according to these standard operating procedures. This will force the operators to set the filling nozzle pressures correctly and wait till the water temperature is at a low level. 7. Bottles crushed in the Capper 1. The use of functional clamps and visible set point-marks on the equipment will ensure that the star wheel is mounted and installed the right way, the first time (discussed in detail in section ). This will in turn ensure that the bottles aren't crushed between the star wheel and the bottle guide. 2. A well-established maintenance program, as stated in section 8.1.1, will prevent the wear and tear on equipment and in turn decrease the tolerance on the star wheel. The suggested improvements made to eliminate the minor stoppages on the Filler are very similar. The majority of the problems experienced on the Filler are caused by old and worn equipment and components. There are smaller problems occurring on the Filler that has other causes than old and worn equipment, but they are in the minority. The implementation of a maintenance program will benefit the company greatly. 59

66 The Unscrambler The suggested improvements to decrease and eliminate the minor stoppages on the Unscrambler are tabulated in Table 13. Table 13 Minor Stoppage Improvements on the Unscrambler Minor Stoppage on the Unscrambler Minor stoppage improvements 1. Unscrambler out of timing 1. Standard operating procedures should be documented and the operators have to be trained to operate the equipment according to these standard operating procedures. This will prevent the operators from operating the equipment manually. 2. A well-established maintenance program, as stated in section 8.1.1, will prevent worn equipment that causes slip in moving components. 3. The maintenance program will ensure that the Unscrambler keeps its timing by decreasing the slip on moving components. 2. Bottles are crushed in the Unscrabler pockets 1. A well-established maintenance program, as stated in section 8.1.1, will prevent the wear and tear on the pocket axis. 2. The relocation of the component storage area from the maintenance stores to the Unscrambler will eliminate the excessive handling of the pockets. This will decrease the damage on the components used on the machine. 3. Unscrabler guide is broken 1. The use of functional clamps to tighten the bottle guide to the Unscrambler frame. 2. Reinforcing the bottle guide with aluminium ribs will prevent the bottle guide from breaking. The same basic problems and solutions were identified on the Unscrambler, as was the case on the Filler. The lack of a maintenance program is an alarming concern at Nestle Waters. 60

67 8.3. Single Minute Exchange of Dies It has been identified in the data and information gathering section that the biggest concern is the long changeover times on Line 1. The objective of SMED in combination with TPM is to decrease the changeover times on Line 1 which will in turn increase the productivity of the production line. Currently there are three different changeovers on Line 1: 1. Changing from one flavour of water to another without changing the bottle size 2. Changing the bottle size without changing the flavour of the water 3. Changing the bottle size as well as the flavour of the water to another flavour The studies done on the three changeovers revealed that the average time it takes for one operator and one artisan to perform each of these changeovers is as follows: 1. Changing the water flavour without changing the bottle size 120 minutes (2 hours) 2. Changing the bottle size without water flavour change 370 minutes (6.16 hours) 3. Changing the bottle size and the water flavour 400 minutes (6.7 hours) The primary reasons for these long changeovers are the fact that most of the setups done on Line 1 are internal setups (performed when the machine is stationary) and that there isn t standardized procedures and components Stage 1: Separating External and Internal Setups The first stage of the SMED methodology is to separate the internal and the external setup operations. The separation of external and internal setups can be done by using checklists. Although the changeovers are almost the same, each of the three different changeovers will be discussed separately for illustration purposes in the first stage Water flavour changeover without the bottle changeover Table 14 lists all the activities that are performed during this changeover and the type of setup classification, i.e. external or internal. There are no changeover activities on the Unscrambler during the flavour changeover due to the fact that the bottle size has nothing to do with the flavour change. Only the activities of the Filler will be illustrated in Table 14. Activities 11, 12 and 14 are currently executed as internal activities although theoretically they are external activities. There is no clear explanation on why these three activities are performed while the Filler is stationary. 61

68 Table 14 Current changeover activities on the Filler Nr. Activity Extenal Internal 1 Screwing CIP cups onto filler points X 2 Removing excess material, caps & water from Filler X 3 Preparing Filler for CIP X 4 CIP X 5 Mixing the next flavour syrup X 6 Transporting the bottle caps X 7 Filling the hopper with caps X 8 Preparing the Filler for the flush X 9 Flushing the Filler X 10 Preparing the Filler for new flavour water X 11 Correcting the Filler programming X 12 Filling the tanks with syrup X 13 Removing CIP cups X 14 Test run X Bottle changeover without the water flavour change The activities that are performed during the bottle changeover and the classification of the current type of setup (external or internal) are illustrated in Table 15 and Table 16. It is necessary to change the components of both the Filler and the Unscrambler due to the change in the bottle size. The classification of the activities performed on the Filler during this changeover is illustrated in Table

69 Table 15 Current changeover activities on the Filler Nr. Activities External Internal 1 Lift/lower buffer tank height X 2 Lift/lower capper head height X 3 Lift/lower shute height X 4 Lift/lower top plate height X 5 Find and transport the components that need to be changed X 6 Find the tools needed for the changeover X 7 Wait for Artisan to assist machine operator X 8 Remove and Install Infeed Scroll (Left) X 9 Remove and Install Infeed Scroll (Right) X 10 Remove and Install Infeed Guide (Left) X 11 Remove and Install Infeed Guide (Right) X 12 Remove and Install bottle clamps X 13 Remove and Install bottle guide X 14 Remove and Install infeed starwheel upper X 15 Remove and Install infeed starwheel lower X 16 Remove and Install intermediate bottle guide X 17 Remove and Install intermediate starwheel upper X 18 Remove and Install intermediate starwheel lower X 19 Remove and Install conveyor bottle guide infeed X 20 Remove and Install conveyor bottle guide outfeed X 21 Remove and Install upper cap starwheel (x2) X 22 Remove and Install lower cap starwheel (x2) X 23 Remove and Install Block X 24 Remove and Install outfeed guide X 25 Remove and Install reject starwheel (x2) X 26 Remove and Install reject bottle guide X 27 Remove and Install outfeed guide (left) X 28 Remove and Install outfeed guide (right) X 29 Remove and Install cap shute guide X 30 Remove and Install cap guide outfeed X 31 Change settings on the programming with the assistance of the artisan X 32 Trial run X 33 Correct problems X The changeover activities performed on the Unscrambler during this changeover are categorized in Table

70 Table 16 Current changeover activities on the Unscrambler Nr. Activities External Internal 1 Stop the unscrambler X 2 Locate the parts that need to be changed X 3 Transport the pockets to the unscrambler X 4 Find the tools needed for the changeover X 5 Wait for Artisan to assist machine operator X 6 Remove the 'old pockets' X 7 Install the 'new pockets' X 8 Adjust pocket openings X 9 Change settings on the programming with the assistance of the artisan X 10 Trial run X 11 Correct problems X Bottle changeover with Water Flavour change The bottle and flavour changeover is the combination of the first two changeovers. The sequence of the changeover activities on the Filler is different from the first two changeovers but the changeover on the Unscrambler is exactly the same. The components on the Filler and the Unscrambler have to be changed to accommodate the new bottle size and the Filler has to be rinsed with chemicals to remove traces of the previous flavour from the system. The classification of the activities performed on the Filler during this changeover is a combination of the Table 15 and Table 14. The changeover activities performed on the Unscrambler during this changeover are exactly the same as in the bottle changeover. These activities are categorized in Table Stage 2 & 3: Convert Internal Setups to External Setups and Streamline Setup activities The second stage of the SMED methodology involves the process of converting the internal setup activities to external setup activities. Techniques that can be utilized to convert the internal activities to external activities are as follow (R. I. McIntosh et al, 2000): Preparing operating conditions in advance Function standardization Utilizing intermediary jigs 64

71 The third stage of the SMED methodology entails the streamlining of the external setup activities and the remaining internal setup activities in the changeover process. Techniques defined by R.I. McIntosh et al (2000) to streamline the setup activities are: Improving transportation and storage of dies, etc. Implementing parallel operations Using functional clamps Eliminating adjustments Least common multiple system Mechanisation The second and the third stage of the SMED methodology are combined into one stage in this section. The reason for the combination of the two stages is attributable to the fact that the majority of the changeover activities performed on the Filler and the Unscrambler has to be done while the machine is stationary. The safety measures and regulations of Nestle Waters compel any person to stop the machine completely and switch the machine off before changing moving parts inside the machine, making the conversion of internal setup activities to external setup activities a tedious process Water flavour changeover Improvement Suggestions The CIP and the activities that accompany the CIP process are all internal activities which have to be done while the Filler is stationary. CIP is the cleaning of the filling system from excess syrup and flavoured water to ensure that the next flavour doesn t have any traces of the previous flavour that was bottled. The time the CIP and related CIP activities take accumulates to 69 minutes of a total changeover time of 120 minutes. After the CIP has been performed, the filling system has to be flushed out with fresh water to remove the odours and excess chemicals used during the CIP. The time the flushing activities take accumulates to 19 minutes of the total changeover time of 120 minutes. The first suggestion to decrease the changeover time is to eliminate the CIP that is performed during a water flavour change. Instead of performing the CIP, the operator only has to flush the system before the next flavour of water is pumped into the capacity tanks and filling system. A critical analysis was executed to determine if it is possible to eliminate the CIP. The second suggestion is to eliminate the CIP and shorten the flushing activities during the changeover on the Filler. The flushing activities can be shortened by performing the flushing only on the capacity tanks for 7 minutes to remove the excess flavoured water in the tanks. 65

72 Table 14, which is an illustration of all the activities during the current changeover, is converted to Table 17 according to the improvement suggestions mentioned. Table 17 Suggested Water flavour changeover activities The internal activities identified during the current water flavour changeover, mentioned in Table 14, are reduced from eight internal activities down to two internal activities (highlighted in yellow). Activities 1, 2, 3, 6, 7 and 8 are external activities which can be performed while the Filler is in production, thus reducing their time duration to zero. A complete water flavour changeover will take approximately 14 minutes to complete after the suggested improvements are implemented. The result of removing the CIP activities will be that the first cases of 500m bottles (six 500ml bottles per case) or cases of 1.5 litre bottles (four 1.5 litre bottles per case) of flavoured water will have traces of the previous flavour but it will be very small. The consequence of removing the CIP activities and adapting the flushing activities will be the increase in the number of cases that will contain mixed flavoured water from cases of 500ml bottles or cases of 1.5 litres bottles to cases of 500 ml bottles (six 500ml bottles per case) or cases of 1.5 litre bottles (four 1.5 litre bottles per case) depending on the strength of the syrup flavours. These cases cannot be used for retailing purposes due to their mixed taste. The solution to the mixed flavoured water problem is to donate these cases of bottled water to the awareness and educational programs that Nestle is running in the nearby settlements as Nestle Waters Mixed Flavoured Water, instead of donating the pure flavoured water. Special labels can be designed which specify that these bottles of water aren t pure flavours, but tangy new mixed flavours. There will not be any direct cost implications to the company by implementing the suggested improvements during the flavour changeover. The workload of the operator will be smaller, thus giving the operator more time to perform the external activities and eliminating the need 66

73 for a second operator for assistance during the changeover. The only monetary implications that the suggested improvements will have on the company will be the savings made on the chemicals used for the CIP and the increase in the productivity of Line 1 due to the decrease in changeover time and increase in the production. The first suggestion reduces the changeover time from 121 minutes to 29 minutes (a time reduction of 76%), while the second suggestion reduces the changeover time from 121 minutes to 14 minutes (a time reduction of 88.4%) Bottle Changeover Improvement Suggestions During the bottle changeover, the operators of the Filler and the Unscrambler have to wait for artisans to assist them in the physical changing of components on the machines. The components of the machines have to be physically removed and replaced by the operators to accommodate the new bottle size. According to the safety measures and regulations of Nestle Waters, any person who has to replace moving components on a machine, on their premises, has to stop the machine and switch it off completely before commencing with their responsibilities. Due to the safety measures and regulations of Nestle Waters, the majority of the activities performed on the Filler and the Unscrambler during the bottle changeover has to be done while the machines are stationary. This will result in a large number of internal activities that cannot be changed into external activities. Rather than trying to change these internal activities into external activities, the focus will be on simplifying these activities by utilizing the techniques mentioned in stage three. The reduction in the time it takes to remove and replace the moving components will in turn reduce the changeover times. The techniques that are suggested to reduce the changeover times on the Filler and the Unscrambler are: 1. The standardization of outside dimensions, fittings and settings that parts can be exchanged easily 2. Streamline the storage and transport of materials, parts and tools 3. Utilize functional clamps 4. Use colour coding and shadow boarding to eliminate the searching for parts 5. Eliminate adjustments with fixed numerical scales and visible set point-marks 67

74 The first suggestion is to standardize the fittings, outside dimensions and settings of the components on the machines, that the parts and components can be exchanged easily. Figure 29 is an illustration of possible improvements on the Filler bottle controls. Fig. 29 Suggested improvements on the Filler bottle controls The colour coded Self Centering Neck Clamp on the Filler replaces the current Fixed/Movable Jaw Neck Clamp with a Double Sided Self Centering Movable Jaw Neck Clamp. With the improved grasp around the bottle (Figure 30), this neck clamp provides more stability when the neck of the bottle is in the neck clamp jaws, preventing the bottle from buckling out of the bottle control when running the line at high speeds. Fig. 30 Neck Clamps improvements Movable Jaw Current Neck Clamps Fixed Jaw Improved Neck Clamps Both Jaws move and are self centering 68

75 The colour coded One Touch Height Spacer on the Filler (Figure 29) is a simple piece of metal that is pushed in between the neck clamp and the bottom platform to adjust the height setting of the neck clamp to suite the bottle size. This method is easy to use, very quick and very accurate. The bottom platform on the Filler bottle control has to be removed with each bottle changeover to accommodate the different bottle diameters. There are two alternatives to improve this problem: the first is to convert the platform to a quick-change component by equipping the platform with mushroom pins to hold it in position and fitting it with a quick release pin (Figure 29). The second alternative is to combine both bottle diameter patterns on the same fixed platform, as illustrated in Figure 31. Fig. 31 Illustration of the platform with both bottle diameter patterns Currently, there are two sets of pocket openings that need to be replaced with a bottle changeover. The one set has a bigger opening to accommodate the 1.5 litre bottles and the other set is smaller to accommodate the smaller 500ml bottle. Changing these pocket openings is a long process and can be improved by fixing the 1.5 litre shape onto the Unscramble and just clipping on the smaller pocket opening on the 1.5 litre shape. The second suggestion is to relocate all the components that are needed during a changeover and store them in lockable industrial trolleys or stationary storage facilities next to the machine in the production line. One of the biggest concerns is the distance that the operators of the Filler and the Unscrambler have to travel to get the components needed for the changeovers. The operator of the Filler has to travel a distance of 110 meters to collect the needed components from the maintenance stores. 69

76 The distance that the Unscrambler operator must travel is more or less 130 meters to collect the needed components for the changeover. The parts are then transported by hand and forklift to the machines. Figure 32 illustrates the ideal positions for the storage facilities in the production line. Fig. 32 Storage areas for changeover components Shrink Wrapper Palletizing Labelling Machine Rinser Filling Table Slat Conveyor Still Water Bottling Line Filler (Line 2 Filler) Line 1 Filling Machine Scrollers Bottle Capper Storage area for the Filler Air Conveyor Rail Bottle Unscrabler Bottle Shute Storage area for the Unscrambler Elevator Loading Dock for the bottles The storage areas allocated to the Filler and the Unscrambler are situated next to the machines, within two metres and out of the way of the other production lines (not shown in Figure 32). The storage area will consist of mobile trolleys and stationary lockable storage compartments. The trolleys can be used to transport the heavy components to and from the allocated storage area. It is very important that the storage area has to be lockable due to theft at Nestle Waters. Figures 33 and 34 are illustrations of the suggested heavy duty trolleys and storage compartments. 70

77 Fig. 33 Proposed trolley Fig. 34 Proposed storage compartment The storage of the changeover components next to the machines will decrease the travelling distance, the time it takes to search for the components, decrease the possibility of damaging the components and in turn decrease the time it takes to transport the components to the machines. Each operator must be equipped with his/her own toolbox (as illustrated in Figure 24). The tools needed for the changeovers will be stored in the toolbox and the operators have to take full responsibility for the tools. The tools required for each machine is shown in the appendices. The third suggestion is to utilize functional clamps. Currently, star wheels have to be attached to the machine using screw fixings directly onto the frame of the Filler. The process of fixing these components to the Filler frame is a tedious process and can be improved by replacing the screw fixings with stainless steel sub bases which stays attached to the machine. The star wheels are then attached to the hub using a locking collar (Figure 35) Fig. 35 Functional clamp for the starwheels 71

78 The bottle guides are currently fixed to the Filler and Unscrambler frames with five bolts on each side of the bottle guide. The process of tightening each bolt and fixing the bottle guide is a long process and can be improved by reducing the bolts to three on each side and one at the top and bottom side of the bottle guide and replacing the bolts with locking cams as shown in Figure 36. Fig. 36 Locking Cam to fix bottle guides to Filler and Unscrambler Other commonly used functional clamps that can be utilized, include the pear-shaped hole method, the U-slot, the C shaped washer, the split thread, spring stops, and magnets or vacuum suction to remove and replace parts easier. The fourth suggestion is the use of colour coding and shadow boarding to eliminate the searching for parts. There are two different bottle sizes used on the production line: 500ml bottles and 1.5litre bottles. Currently none of the components and tools used during the changeover is colour coded. This makes it difficult to distinguish between the different component sizes. The following colour codes were suggested for the two different bottle sizes to increase visibility of the parts and eliminate confusion: the 500ml bottle components should be coloured bright orange and the 1.5 litre bottle components should be coloured bright blue. These two colours are easily distinguished and easy to spot. Shadow boarding the parts on the storage compartments will enable the operators to identify the different storage areas with ease and eliminate the confusion of where to store which part. Another advantage of shadow boarding is that the operator can easily detect when there are parts or tools missing. The fifth suggestion is to eliminate adjustments with fixed numerical scales and visible set point-marks on the machines. Visible set-points and reference lines on the machines will enable the operators to change parts without difficulty and with ease. The application of fixed numerical scales on equipment will eliminate deviating spaces between star wheels 72

79 and bottle guides or between scrollers. Shortening the threads of bolts will decrease the times an operator has to turn the tool to tighten the nut and fix the component to the machine. Although the majority of activities that has to be performed on the Filler during a bottle changeover cannot be converted from internal set-up activities to external set-up activities, the changeover times of each component can be drastically reduced by implementing the suggested improvement techniques on the Filler. Table 18 shows the changeover activities and the estimated impact the improvement techniques will have on their changeover time duration. The estimated times used in Table 18 established and based on available changeover data from various sources. Table 18 Changeover activities and time durations after changeover improvements 73

80 Activities 1, 28 and 29 are external activities which can be performed while the Filler is in production, thus reducing their time duration to zero. The estimated time that a complete bottle changeover would take on the Filler will approximately be 152 minutes. This will be an estimated reduction of 58% on the changeover time of the Filler. The estimated changeover times of the Unscrambler after the implementation of the improvement techniques suggested are shown in Table 19. All estimated values are determined and based on relevant available changeover data from other resources. Table 19 Changeover activities and time durations after changeover improvements Nr. Activity Extenal Internal Time duration 1 Stop the unscrambler X 1 2 Remove the 'old pockets' X 59 3 Install the 'new pockets' X 62 4 Adjust pocket openings X 14 5 Change settings on the programming with the assistance of the artisan X 7 6 Trial run X 7 Activities 1, 5 and 6 are external activities which can be performed while the Unscrambler is in production, thus reducing their time duration to zero. The estimated time duration of a complete bottle changeover would take on the Unscrambler will approximately be 135 minutes. Unscrambler. This will be an estimated reduction of 60% on the changeover time of the Bottle Changeover and Flavour Change Improvement Suggestions The changeovers that are performed during this changeover are a combination of the changeovers discussed in section and The suggested improvements that have to be made during this changeover will be the same as is discussed in section and Evaluation and Recommendation The suggested improvements and solutions to the identified problems occurring on Line 1 will be evaluated in this section Equipment Failures and Breakdown Solutions The implementation of a preventive maintenance program will increase the productivity and machine life of Line 1 and decrease the equipment failures and breakdowns experienced on the line. The elimination of the breakdowns on Line 1 by maintaining the equipment on a regular basis will result in a decrease in rate losses and minor stoppages which in turn will increase the productivity. 74

81 The P-M analysis revealed that worn equipment plays an enormous role in the occurrence of minor stoppages on Line 1. The maintenance of the equipment will ensure that tolerances on the components will not develop and in turn decrease the minor stoppages caused by worn equipment. The cost of implementing a TPM program or a preventive maintenance program at Nestle Waters cannot be established beforehand. A detailed analysis should be performed to establish what type of maintenance requirements each machine on the line requires, which parts will have to be replaced and repaired, the interval between maintenance activities on each machine and the number of employees needed to perform the maintenance operations. The results of the studies and surveys conducted by Wireman (1991) and Nakajima (1988) on the impacts of the implementation of TPM and the mentioned maintenance programs are shown in Table 20. Table 20 Examples of TPM Effectiveness (Recipients of the PM prize) Category Examples of TPM Effectiveness Productivity % increase in labour productivity 30-80% increase in rates of operation % decrease in equipment breakdowns Quality % decrease in defects 30-50% decrease in clients claims Costs 30-50% decrease in labour costs % decrease in maintenance costs 30 % decrease in energy costs Inventory 50% reduction of inventory levels % increase in inventory turns Safety Elimination of environmental and safety violations Morale 200% increase in improvement suggestions by employees According to the results shown in Table 20, the implementation of a TPM or at least a maintenance program will have huge beneficial impacts on the productivity of the production lines, quality of the product, costs incurred during production, inventory levels, safety of the plant and the morale of employees Minor Stoppage Solutions A great deal of the elimination process of minor stoppages is related to worn equipment that can be corrected by the maintaining of equipment as discussed in section In Table 20 it is shown that the implementation of a maintenance program will decrease machine breakdowns by %. This suggests that there will be a related decrease in minor stoppages on the equipment as well. 75

82 The objective of TPM is to decrease minor stoppages near to elimination. Minor stoppages will never be entirely eliminated on a production line. Table 21 is an example of the impact that a decrease in minor stoppages would have on a year s production capacity. Table 21 Increased production capacity (Litres Water) with decrease in Minor Stoppages Production Rate (Bottles/Hour) Minor Stoppage 500ml 1.5 litres Decrease (%) The total minor stoppage time during the production year of 2007 amounted to 310 hours. Table 21 shows that with a decrease of 50% in minor stoppages, the production capacity will increase annually with litres of flavoured water when 500ml bottles are bottled at bottles per hour or the production capacity will increase annually with litres of flavoured water when 1.5 litre bottles are bottled at bottles per hour. The production rate will steadily increase as the minor stoppages and equipment breakdowns decrease Changeover Solutions Changeovers contribute for 27.2% of the total production hours available per annum on Line 1. That amounts to around 800 hours of non-productive time during a production year. The production capacity lost, at bottles per hour for the production of 500ml bottles, will amount to litres of flavoured water OR the production capacity lost, at bottles per hour for the production of 1.5 litre bottles, will amount to litres of flavoured water Flavour Change Improvements Figure 37 is an illustration of the impact that the suggested improvements will have on the production capacity of Line 1 during one changeover. 76

83 Bottles Fig. 37 Production capacity increase with one changeover Increase in Production per changeover (Litres) suitable for Retailing purposes Current Flavour Changeover Flavour Changeover without CIP Flavour Changeover without CIP and Flush Litres (500ml bottles/hour) Litres (1.5litre bottles/hour) Changeover Improvement Suggestions It is clear, from Figure 37, that the best alternative to improve the flavour changeover activities is to eliminate the CIP and perform the normal flush on the Filler. Although it sounds attracting to have a changeover time of 14 minutes, the amount of mixed flavoured water increases dramatically due to the fact that the system is not flushed properly. By eliminating the CIP, the production capacity will increase by litres of flavoured water per changeover. If the flavour of the water is changed three times per week, every week of the year, the production capacity per production year will increase by litres per year. The CIP cannot be eliminated entirely due to health and safety reasons and this forces the operators to performed the CIP during predetermined changeovers for these health and safety reasons Bottle Changeover Solutions The suggested improvements that could be implemented on the Filler and the Unscrambler during the bottle changeover will decrease the changeover times of these machines to an estimated 152 minutes and 135 minutes respectively. 77